利用双向循环链表进行显示更新

     这个程序目前的的功能是显示10个节点里面的内容。这里假设能从一个socket中不断地读取数据（如何读取这里忽略），要

对这些数据进行显示和过滤。显示时最新更新的显示在最前面，程序实现后前过滤关键字满足关系运算。现在的状态是十个节点

可以简单过滤，显示最新。下面是源码：

//file.h,the fuctiong's header file// #pragma once #include <stdio.h> #include <stdlib.h> #include <time.h> #include <string> #include <stdio.h> #include <malloc.h> #define null 0 using namespace std; #define LEN sizeof(struct mon) //定义个一个结构体，存储从socket读取来的内容// struct mon { int num; bool delet_falg; char tmp[100]; struct mon *next; struct mon *subnext; }; void delay(int ns); void create(int nn); void print(struct mon *head); void set(int mm); void update(); void filter(char *filter); //*************************************************************************************// //create.cpp file ///// //建立双向循环链表，用于存储内容、显示和更新////// #include "file.h" /////next is in the one dirction and the subnext is in the nagetive dirction/// ////and the dirction is the loop //// void create(int nn) { extern struct mon *head, *tail; // mon结构指针，全局变量 extern time_t t; char *str[15] ={ "goo hello world!","good how are you?","good moning!","what wrong with you?","this is every good !","noting is moreimportant .","he is heer!","I want to have a job.","I miss you!","can I have a sit here?","why this can be wrong?"}; int i; struct mon *p,*q; p=(struct mon *) malloc(LEN); p->num = 1; for (i=0;i<strlen(str[0]);i++) p->tmp[i] = str[0][i]; p->tmp[strlen(str[0])] = 0; p->delet_falg = false; p->next=null; p->subnext=null; head=p; q=p; for(i=2;i<=nn;i=i+1) { p=(struct mon *)malloc(LEN); p->num=i; for (int j=0;j<strlen(str[i-1]);j++) p->tmp[j] = str[i-1][j]; p->tmp[strlen(str[i-1])] = 0; p->delet_falg =false; q->next=p; q->subnext=p; q=p; p->next=null; p->subnext=null; } tail = q; tail->next=head; tail->subnext=head; ///q is the first one and p is pointer to the second one // ///next is in one direction and subnext is the negative direction/// q = head; //first one p = head->next; //second one for(int i = 0 ; i<10;i++) { p->subnext = q; p=p->next; q=q->next; } ////Traversal( means for in all ) /// ///分别正向遍历和反向遍历这这10个节点////// p = head; for(int x =0;x<10;x++) { printf("%d : %s/n",p->num,p->tmp); p = p->subnext; } p = head; for(int x =0;x<10;x++) { printf("%d : %s/n",p->num,p->tmp); p = p->next; } } //*************************************************************************************// // delay.cpp 实现延时函数///// #include "file.h" ///the delay function . void delay(int ns) { extern struct mon *head, *tail; time_t start_time, cur_time; time(&start_time); do { time(&cur_time); } while((cur_time - start_time) < ns); } //************************************************************************************// ////filter.cpp/////////////// ///过滤，当检测到节点数据里包含过滤关键字时设置标志位/// #include "file.h" void filter(char *filter) { extern struct mon *head, *tail; struct mon *p = head; for(int k = 0; k<10; k++) { int f = 0; for(int j=0;j<80;j++) { if(filter[f]==p->tmp[j]) { if(f ==(strlen(filter)-1)&& (p->tmp[j+1]==32||p->tmp[j+1]==63||p->tmp[j+1]==33) ) { p->delet_falg = true; break; } f++; continue; } else f = 0; } p=p->next; } } //*************************************************************************************// ////print.cpp////// #include "file.h" void print(struct mon *head) { struct mon *p = head; system("cls"); for (int i=0;i<10;i++) { if(!p->delet_falg) printf("%d: %s/n",p->num,p->tmp); p = p->subnext; } } //*************************************************************************************// //update.cpp,更新// #include "file.h" ///when get new data ,putting it in node by "next",(over write the oldest data) ///then this node is the newest,so we need put it out in the front of screen. ///In order to do this we need use the subnext to for in all the node by negative ///dircation(this part is in the funtion print()).In all,the over write is in one ///dircation by next,and the traversal is in the negative dircation by subnext. ///set p is for the new data,and over wrinte it.set q is to traversal all the node ///then we can filter nodes include the special world . void update() { extern struct mon *head, *tail; extern time_t t; struct mon *p; struct mon *q; p = head; while(1) { print(p); p = p->next; delay(3); } } //*************************************************************************************// //main.cpp// #include "file.h" struct mon *head, *tail; // mon结构指针，全局变量 char f_str; void main() { int n; head = null; printf("please input the number 10 of node you want to create :/n"); scanf("%d",&n); create(n); getchar(); printf("put in what you want to fliter:/n"); gets(&f_str); filter(&f_str); update(); }

 

在创建节点时，这个程序现在输入10能够正确的显示，更新，过滤。如果想创建更多的节点可以修改相应的程序，用以实现。

 

输入：

 

输出：每一秒刷新一次，从结果看出已经过滤了good这个关键字

 

这个程序的关键点在双向循环链表，新读的数据按一个方向存储，显示数据按另一个方向因为显示是从新向旧显示，更新是从旧向新更新，

覆盖最旧的成为最新的。后期的改进是要加入从socket读取ip数据报，并且需要一个gui界面，其实做了一部分，后期还涉及到多线程之

类的东西（用Qt做的gui）.一定会找时间做完贴上来。